The invention relates to an element for the transfer of gas into liquids, in particular, for the transfer of oxygen in sewage treatment plants, with a porous gas transfer member into which gas is introduced via a feeder line and after passage through the porous gas transfer member is given off in the form of gas bubbles into the liquid surrounding the gas transfer member.
Such gas transfer elements are, for example, of platelike or disk-shaped configuration, with the gas bubbles mainly exiting from the upper boundary surface of the gas transfer member. It has been found that the exiting bubbles are subject to a constriction as they rise, i.e., the bubbles exiting from the total surface are compressed during their ascent onto a cross section which is substanitally smaller than the cross section of the surface of the platelike gas transfer member. In this way, a number of bubbles come into contact with one another and form considerably larger bubbles (bubble cluster) which results in a substantial reduction in the available diffusion surface of the bubbles, which is of prime importance in the transfer of the gas into the liquid. This clearly decreases the efficiency of the transfer of the gas into the surrounding liquid, which is extremely disadvantageous, particularly in the field of sewage treatment where atmospheric oxygen should be introduced as efficiently as possible into the liquid to be purified.
The construction for installing pipe aeration systems in sewage treatment plants has hitherto involved a great deal of expenditure for both the aids and the assembly (stub supply lines, four-edged distributors, seals, etc.). Also, such constructions are subject to particularly strong corroding influences, which led to the use of expensive high-grade steel pages and devices.